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H. G. LEONARD.

DIFFERENTIAL. i

. APPLICATION FILED MAR. 21- 1917.

Patented Aug. 12, 1919.

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WITNESSES IN V EN TOR.

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H. G. LEONARD.

DIFFERENTIAL.

ION H 1,312,856. PatentedAug.12,1919. 4SHEETS SHEET 2.

IN VEN TOR.

WITNESSES:

How rd y Leonard. BY ZMQZM z ATTORNEYS.

H. G. LEONARD.

DIFFERENTIAL.

APPLICATION FILED MAR. 21. 1911.

Patented Aug. 12, 1919.

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DIFFERENTIAL.

APPLICATION FILED MAR. 21. 1911.

1 31 2,85 Patented Aug. 12, 1919.

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H ref-*3 1. O l- IE IEYSZIIL- I INVENTOR. v WITNE H0 ward Leonard I I BY 6 (32 v Arroi HOWARD G. LEONARD, OF JACKSON, MICHIGAN.

DIFFERENTIAL.

Specification of Letters Patent.

Patented Aug. 12, 1919.

Application filed March 27, 1917. Serial No. 157,851.

To all whom it may concern:

Be it known that I, HOWARD G. LEONARD, a citizen of the United States, residing at Jackson, county of Jackson, State of Michigan, have invented certain new anduseful Improvements in Differentials, of which the following is a specification.

This invention relates to differentials.

The main objects of this invention are:

First, to provide an improved differential which is strong, durable, and reliable.

Second, to provide an improved differential having these advantages which is simple and economical in its parts and easily assembled.

Further objects, and objects relating to structural details, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification. The invention is clearly defined and pointed out in the claims.

w A structure which is a preferred embodiment of my invention is clearly illustrated in the accompanying drawing, forming a part of this specification, in which:

Figure I is a detail longitudinal section of the preferred embodiment of my invention, portions of the driving shaft and driving axle being broken away.

Fig. II is a detail transverse section on a line corresponding toline 2-2 of Fig. I.

Fig. III is a detail transverse section on a line corresponding to line 33 of Fig. I.

Fig. IV is a longitudinal section ofa modified form of my invention involving the use of bevel gears.

Fig. V is a detail transverse section on a line corresponding to line 55 of Fig. IV.

Fig. VI is a .detail section on a line corresponding to line 66- of Fig. IV.

Fig. VII is a detail longitudinal section of another embodiment of my invention involving the use of worm gears.

Fig. VIII is a detail transverse section taken on a line corresponding to line 88 of Fig. VII.

Fig. IX is an enlarged detail section taken on a line corresponding to line 9-9 of Fig. VIII.

Fig. X is an enlarged detail section taken on a line corresponding to line l010 of Fig. VII, showing the limiting stop used in this embodiment. V

Fig. XI is an enlarged detail side elevation. of one of the driving pinions used in this embodiment, of my invention.

, In the drawing similar reference characters refer to similar parts throughout the several views, and the sectional views are taken looking in the direction of the little I arrows at the ends of the section lines. Referring to Figs. I, II and III of the drawing, which disclose one embodiment of my invention, the reference character 1 designates the driven shafts or members, which are, in the'embodiment illustrated, the sections of a driving or live axle of a motor vehicle.

A driven gear 2' is fixed upon the inner end of each axle section, which is squared or otherwise shaped to provide a secure driving connection for the gears thereto.

In the embodiment illustrated the gears are provided with sleeve-like extensions 3 constituting bearings for other parts. Rotatably mounted upon these bearings is a pair of yokes 4 comprising oppositely fixed arms 5. Inwardlyprojecting stub shafts 6 are mounted on the outer ends of these arms. Pinions7 are mounted on these shafts to mesh with the gears 2. For a purpose which will appear as the description proceeds these pinions have long teeth 8 and short teeth 9 disposed alternately, the short teeth being bearing 3. The head 12 is detachably secured by means of the bolts 13.

' An annular beveled gear 14 is mounted upon the driving member 10, which is provided with a flange 15 to receive the gear.

tegrally with the driving member, but I find the form illustrated a practical one. The driving member is connected to the power or propeller shaft 17 by means of the gear 16 meshing with the gear 1 Secured to the inner periphery of the driving member 10 on opposite sides of each of the pairs of driving pinions 7 are the driving lugs 18. These driving lugs are, in the embodiment illustrated, secured to the driv "The gear 14 may, if desired, be formed insections or driven members.

ing member by means of tongues 19 and grooves 20 and screws 20. The length of the lugs 18 is slightly less than the distance between the short teeth on the opposed pinions 7. \Vhen the driving member 10 is rotated so that the driving lugs 18 occupy the position indicated by the dotted line 21,see Fig. II, the pinions 7 are locked against rotation and the power is transmitted to the driven member.

From an inspection of Fig. II, it will be clear that if all the teeth of the driving pinion 7 extended entirely thereacross the driving lug 18 would merely engage the extreme ends of the teeth, but by cutting away portions of alternate teeth the driving lugs engage the full length teeth at the roots thereof, whereby the danger of breakage is considerably lessened. IVhen the driving member 10 is driven in the reverse direction the driving lugs 18 occupy the position in dicated by the dotted lines 22.

hen a vehicle equipped with my improved differential is turning a corner or when for any other reason one of the axle sections 1 is caused to rotate at a speed in excess of the speed of the driving member 10 the driving pinions 7 are carried forward until the teeth thereof are disengaged from the driving lugs, whereupon the driving pinions 7 may turn idly.

In order to prevent the driving pinion of one axle section from engaging one set of driving lugs while the driving pinions of the other section are in en agement with the other set of driving lugs, Iprovide means for limiting the movement of one axle sec tion relative to the other. In the embodiment of my invention disclosed in Figs. I, II and III, this limiting means comprises a lug 23 formed on the end of one of the stub-shafts 6 which coacts with the sides of a recess 24 in the adjacent end of the opposed stub shaft. The proportions of the lug 23 and the recess 24: are such that one of the sections 1 may move relative to the other sufiiciently to disengage its driving pinions from the driving lug, but it cannot move far enough to engage the opposite set of driving lugs.

With this arrangement of parts a positive drive is provided, that is, the power is applied to the slowest driven wheel when they are not revolving together. The advantage of this is apparent, as one of the main objections to the type of differential commonly used, is that when one wheel loses traction the other stops.

In the modified form of my invention, which is illustrated in Figs. IV, V and VI, the beveled gears 25 are fixed to the axle Bevel driving pinions 26 are mounted upon the stub shafts 27 to mesh with the driven gears 25. The stub shafts 27 are disposed radially on the inwardly projecting arms 28 of the yokes 4. The means for locking the driving pinions against rotation comprise pins or lugs 29 secured to the outer ends thereof, which are adapted to engage with the ends of the driving lugs 30 whereby the driving pinions are held against rotation and the axle sections are rotated with the driving member 10' which is somewhat modified in form.

To limit the rotation of .one axle section relative to the other the end of one of the yoke extensions 28 is provided with a slot 31, the sides of which are engaged by the tongue 32 forming a part of the opposite extension.

In the embodiment of my invention illustrated in Figs. VII to XI, inclusive, the driven gears are in the form of worms 33.

The yokes & are provided with inward ex tensions 34.- which support the opposite ends of the shafts 35 for the worm driving pinions 36. The driving pinions 36 have spiral locking lugs 37 secured to each end thereof. The lugs 37 are inclined in opposite directions, as shown in, Fig. XI. This is necessary, since when the driving member is revolving in opposite directions the driving pinion would also revolve in opposite directions and the locking lugs must, therefore, be inclined in opposite directions also.

Interlocking tongues 35 formed on the inner sides of the extensions 34, as shown in Figs. VII and X, act as stops to limit the rotation of one yoke relative to the other.

With the parts in the position shown in Fig, VIII, when the driving member rotates to therleft the lugs 37 on one end of the driving pinions engage the outer ends 38 of the driving lugs 39. INith the parts in the position shown in Fig. VIII, when the driving member is rotated to the right the lugs on the opposite ends of the pinions will engage with the inner ends. 40 of the spaced driving lugs 11. I

With these embodiments and adaptations of my invention illustrated it is believed that the general application thereof to meet varying structural conditions and requirements will be fully understood.

I desire to be understood as claiming my improvements in the embodiments illustrated as well as broadly within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a structure of the class described, the combination with alined axle sections, of driven gears fixed thereto, a yoke rotatably mounted upon each of said axle sections, opposed stub shafts carried by said yokes, pinions rotatably mounted in pairs upon said stub shafts and meshing with said driven gears, a driving member rotatably mounted upon said axle sections, driving lugs secured to said driving member on 0pposite sides of each pair of adjacent pinions, and slightly spaced therefrom in the neutral position of said pinions, the inner portions of alternate teeth on said pinions being cut away to permit said driving lugs to engage the remaining teeth, one of said stub shafts being provided with a recess at its inner end, and the opposite stub shaft being provided with a lug adapted to contact with the sides of said recess and limit the rotation of one yoke relative to the other, as specified.

2. In a structure of the class described, the combination with alined axle sections, of driven gears fixed thereto, a yoke rotatably mounted upon each of said axle sections, opposed stub shafts carried by said yokes, pinions rotatably mounted in pairs upon said stub shafts and meshing with sald driven gears, a driving member rotatably mounted upon said axle sections, driving lugs secured to said driving member on opposite sides of each pair of adjacent pinions, and slightly spaced therefrom in the neutral position of said pinions, one of said stub shafts being provided with a recess at its inner end, and the opposite stub shaft being provided with a lug adapted to contact with the sides of said recess and limit the rotation of one yoke relative to the other, as specified. In witness whereof I have hereunto set my hand and seal in the presence of two wit nesses.

HOWARD G. LEONARD. [L. s.] Witnesses:

H. M. LEONARD, C. W. MARTIN.

Copies of this patent may be obtained for five cents each; by addressing the "Commissioner of I'atents, Washington, D. G. 

